Pressure regulator for high pressure oil and gas wells



Oct. 25, 1966 L. DAVIS 3,280,839

PRESSURE REGULATOR FOR HIGH PRESSURE OIL AND GAS WELLS Filed Oct. 9, 1964 2 Sheets-Sheet 1 INVENTOR PRESSURE REGULATOR FOR HIGH PRESSURE OIL AND GAS WELLS Filed OCT 9, 1964 L. DAVIS Oct. 25, 1966 2 Sheets-Sheet 2 INVENTOR Z. 0 0/5 0/1 v/s ATTORNEY med 4 ..H...

"I. f 6 7 T H 0 6 4 a V 358 a. V 4 K X V V M 2 All K4 5 @A? \xfi/ a /fl fix /md :rw w t 7 v 8 United States Patent 3,280,839 PRESSURE REGULATOR FOR HIGH PRESSURE OIL AND GAS WELLS Louis Davis, 5211 Bell St., Corpus Christi, Tex. Filed Oct. 9, 1964, Ser. No. 402,764 2 Claims. (Cl. 137-494) This invention relates to a regulator adapted to be disposed in the tubing of a high pressure oil or gas well to substantially reduce the pressure above the regulator in the tubing and at the wellhead.

A primary object of the invention is to provide a regulator which by holding the pressure in the bottom of a well beneath the regulator will prevent salt water from breaking into the oil or gas sand, to thereby prolong the life of the well.

Another object of the invention is to provide a regulator which will function as a valve in the bottom of the well, when the well is shut in at the top, or which will reduce the flowing pressure of the well when it is open at the top.

A further object of the invention is to provide a regulator which may be run into a well tubing on a wire line and removed from the tubing in the same manner without killing the well.

Another object of the invention is to provide a pressure regulator which is set in a well tubing by means of a conventional setting tool or anchoring device.

Various other objects and advantages of the invention will hereinafter become more fully apparent from the following description of the drawings illustrating presently preferred embodiments thereof, and wherein:

FIGURE 1 is a fragmentary substantially central vertical sectional view, partly in side elevation, showing the lower portion of a well casing containing a well tubing in which a preferred embodiment of the regulator is disposed;

FIGURE 2 is an enlarged substantially central longitudinal sectional view of the regulator and a part of the setting tool, shown broken away;

FIGURES 3 and 4 are cross sectional views of the pressure regulator, taken substantially along planes as indicated by the lines 3-3 and 44, respectively, of FIG- URE 2;

, FIGURE 5 is a view similar to FIGURE 1 but showing another embodiment of the regulator;

FIGURE 6 is a longitudinal substantially central sectional view on an enlarged scale of the regulator of FIG- URE 5 with a part of the setting tool shown broken away; and

FIGURES 7 and 8 are cross sectional views of the regulator taken substantially along planes as indicated by the lines 77 and 88, respectively of FIGURE 6. Referring more specifically to the drawings, and first with reference to FIGURES 1 to 4, the pressure regulator, designated generally 10 and comprising the invention, is shown in FIGURE 1 disposed in the lower portion of a conventional well tubing 11, somewhat above and spaced from the open bottom 12 thereof. The lower portion of the tubing 11 is shown disposed in the lower part of a conventional well casing 13, the lower end of which is sealed as by cement plug 14. The lower part of the casing 13 is submerged in a subsurface stratum 15 of oil or gas sand, and said part of the casing 13 is provided with perforations 16.

The pressure regulator 10 is supported detachably in {the tubing 11 by a conventional setting tool or anchoring device 17 which is adapted to be lowered into the well tubing 11 in a conventional manner by a wire line, not shown, and detachably anchored therein at any desired level by means of its expansible clamping element 18. The setting tool 17 includes a length of pipe or tube 19 3,280,839 Patented Oct. 25, 1966 carrying annular packing members 20 which engage and seal the well tubing 11 around the pipe 19, to prevent gas or liquid from the bottom of the well from passing upwardly through the tubing 11 except by passing through the regulator 10 and the pipe 19.

As seen in FIGURE 2, the regulator 10 includes a coupling sleeve 21, constituting the upper end thereof, having a bore 22 extending longitudinally therethrough. The upper end of the bore 22 is enlarged and internally threaded, as seen at 23, to threadedly receive an externally threaded lower end 24 of the pipe 19, by which the regulator 10 is detachably connected to and suspended from the setting tool 17, with the bore 22 in registration with the bore 25 of the pipe 19. Coupling 21 has an externally restricted threaded lower end 26 which threadedly engages in the enlarged internally threaded upper end 27 of the bore 28 of an elongated body member 29 of the regulator 10. The body 29 has a restricted bore portion or port 30 which opens through its otherwise closed lower end 31 and which communicates with the lower end of a bore 32. The upper end of the bore 32 opens into the lower end of the bore 28 and is smaller in cross section than the bore 28 and substantially larger in cross section than the port 30. The port 30 and bores 28 and 32 are disposed axially of the body 29.

A valve 33 includes a tubular member 34 of circular cross section the lower portion of which has a relatively close fitting sliding engagement in the bore 32. The upper end of the tubular member 34, which is disposed in the bore 28, is externally enlarged to form a piston 35 which has a close fitting sliding engagement in the bore 28, which thus forms a cylinder for said piston. The bore 32 forms a cylinder for a closed lower end 36 of the tube 34 which forms a piston. The tube 34 has a series of circumferentially spaced inlet ports 37 which are disposed above and spaced from the piston 36; and the body 29 has a series of circumferentially spaced inlet ports 38 all of which communicate with an enlarged portion 39 of the bore 32, which is disposed beneath and spaced from the cylinder 28. The body 29' has annular grooves 40 which open into the cylinder 32 above and beneath its enlargement 39, each of which contains an O-ring 41 for sealing off the cylinder 32 around the tube 34. A compression spring 42 is contained in the upper portion of the cylinder 28 and has its upper end bearing aagainst the lower end of the coupling part 26 and its lower end bearing on the head of the piston 35.

Oil or gas, as indicated by the arrows 43, under considerable pressure will enter the well casing 13 from the stratum 15 through the perforations 16 and will pass into the well tubing 11 through its open lower end 12. A part of the oil or gas will enter the lower end of the cylinder 32 through the inlet port 30, as seen in FIG- URE 2. The pressure thus produced in the lower end of the bore or cylinder 32 will impinge against the piston 36 for moving the valve 33 upwardly to its open position as seen in full lines in FIGURE 2, in which the inlet ports 37 thereof are in communication with the bore portion 39, so that the oil or gas under pressure can pass inwardly through the inlet ports 38 and through the inlet ports 37 into the bore 44 of the tube 34. As the valve 33 moves upwardly to its open position, the piston 35 moves upwardly in the cylinder 28 and creates a partial vacuum in the lower part of said cylinder beneath the piston, which, in combination with the compression spring 42 urges the valve 33 downwardly from its open position toward a closed position as seen in dotted lines in FIGURE 2.'

The gas or oil after entering the bore 44 passes upwardly therethrough into the upper part of the cylinder 28 and then through the bores 22 and 25 into the part of the well tubing 11 which is disposed above the setting tool 17.

The cylinder 28 is substantially larger in cross section than the bores 22 and 25. Thus, a back pressure is developed by this oil or gas in the cylinder 28 above the piston 35. Since the area of the head of the piston 35 is greater than that of the piston 36, a pressure in the upper part of the cylinder 28 substantially less than the pressure in the lower part of the cylinder 32, will combine with the force of the spring 42 and the vacuum in the lower part of the cylinder 28 to force the valve 33 downwardly for moving the ports 37 out of registration with the chamber 39 to close the valve 33. As the pressure diminishes in the upper part of the cylinder 28, the valve 33 will return to its open position of FIGURE 2 to allow additional oil or gas to enter the bore 44. Thus, the regulator will permit a continuous flow of the gas or oil from the stratum through the well tubing 11 in substantial volume but at a greatly reduced pressure relative to the pressure thereof in the lower end of the well casing 13. Springs 42 of different strengths may be utilized for varying the ratio of the pressures beneath and above the regulator 10, or the extent that the coupling portion 26 is screwed into the portion 27 can be varied for varying the pressure exerted by the spring 42. As seen in full lines in FIGURE 2, the spring 42 is substantialy solid in the open position of the valve 33, so that the valve cannot be moved upwardly past this position by the pressure in the chamber 32 sufficiently to close the valve on its upward stroke and after the valve has opened.

FIGURE 5 shows another form of the regulator, designated generally 45, which is supported in the well tubing 11 by the setting tool 17, in substantially the same location with respect to the lower end 12 of the well tubing, as the regulator 10'.

The regulator 45 includes a coupling member 46 constituting its upper end, an elongated body member 47 constituting the lower end thereof, and an intermediate tubular member 48. The upper coupling member 46 corresponds with the coupling member 21 and has an internally threaded portion 49 opening outward of its upper end in which the threaded lower end 24 of the pipe 19 threadedly engages. Tubular member 28 has an enlarged internally threaded upper end 50 to threadedly receive the externally threaded restricted lower end 51 of the coupling member 46. The tubular member 48 has a restricted axial bore 52 which opens through the lower end thereof and which opens at its upper end into the larger axial bore portion 53, to form an upwardly open valve seat 54 where the bore portion 52 opens into the bore portion 53. The upper end of the bore portion 53 opens into the lower end of the internally threaded open upper end 50 and is smaller than said portion 56.

A ball valve 55, of smaller diameter than the bore portion 53 and of larger diameter than the bore portion 52 is disposed in said bore portion 53 and rests on the seat 54. A compression spring 56 has its upper end bearing against the lower end of the coupling part 51 and its lower end bearing on the ball 55. The coupling member 46 has a bore portion 57 in its lower part which communicates with the bore portion 53' and with the bore 25 of the pipe 19.

The body 47 has a closed lower end 58 and a bore 59 which extends upwardly therethrough from said closed lower end. The upper end of the bore 59 opens into a larger bore portion 60 to provide an upwardly opening valve seat 61. The upper end of the bore portion 60 opens into the larger internally threaded upper bore portion 62, which opens outwardly of the upper end of the body 47. Tubular member 48 has an externally threaded restricted lower part 63 which threadedly engages in the portion 62. A ball valve 64 is disposed in the bore portion 60 On the valve seat 61. A compression spring 65 has its upper end bearing against the lower end of the part 63 and its lower end bearing on the ball valve 64. Two inlet passages 66 extend downwardly in diverging rela- 4 tion from the bore 59 and open outwardly of the body 47.

Oil or gas from the substratum 15 enters the lower part of the well casing 13 through its perforations 16 and passes upwardly into the well tubing 11 through its open lower end 12, as indicated by the arrows 43. The oil or gas enters the bore 59 through the inlet ports or passages 66, as indicated by the arrows 43 in FIGURE 6. When the pressure in the bore 59 becomes sufficient to overcome the pressure of the spring 65, the valve 64 opens to permit the bores 60 and 52 to be pressurized. When the pressure becomes sufiicient in the space 'between the ball valves 55 and 64 to overcome the pressure of the spring 56, the ball valve 54 will open to allow the oil or gas to pass into the bore portions 53 and 57 and thence through the pipe 19 back into the well tubing 11 above the setting tool 17. The pressure in the body 47 between the valves 55 and 64 acts with the spring 65 for urging the valve 64 to a closed position, and the pressure in the well tubing above the upper valve 55 acts with the spring 56 for urging the valve 55 to a closed position, so that the pressure of the oil or gas above the valve 55 is substantially less than the pressure in the bore 59. Thus, the oil or gas above the setting tool 17 and at the wellhead will be substantially less than the pressure below the lower valve 64. However, while the regulator 47 will substantially reduce the pressure of the oil or gas it will not appreciably reduce the volume of the flow. Obviously, springs 56 and 65 of different strengths can be employed for varying the ratio between the pressure below the valve 64 and the pressure above the valve 55; and the parts 51 and 63 can be adjusted in the portions 50 and 62, respectively, for varying the pressures of the springs 56 and 65.

By substantially reducing the pressure of the oil or gas at the wellhead over the pressure thereof below the regulator, salt water will be prevented from breaking into the stratum 15 to prolong the life of the well; and the reduced pressure at the wellhead will prevent freezing and eliminate the necessity of utilizing heaters.

Various other modifications and changes are contemplated and may obviously be resorted to without departing from the function or scope of the invention as hereinafter defined by the appended claims.

I claim as my invention:

1. A regulator adapted to be mounted in a tubing of a well for reducing the pressure of a well fluid in the tubing above the regulator relative to the pressure thereof beneath the regulator, said regulator comprising a body having a passage for the fluid including an inlet and an outlet disposed above the inlet, a valve mounted in the. passage for up-and-down movement, a spring contained in the passage for urging the valve downwardly to a closed position for shutting off the fluid flow between the inlet and outlet and to prevent movement of the valve upwardly beyond a fully open position, said passage including a chamber into the upper end of which said valve extends, said chamber being adapted to be pressurized by the pressure of the well fluid to displace the valve upwardly to an open position to permit the fluid to pass upwardly through said passage from the inlet to the outlet while the pressure in the chamber is greater than the combined pressure of the fluid above the valve and the pressure of said spring, said valve comprising an elongated tubular member having a closed lower end defining a lower piston, said chamber constituting a restricted lower portion of the passage in which said piston is slidably mounted, said chamber having an open lower end opening outwardly of the body beneath the lower piston,

said inlet opening into the passage above said lower piston, said passage including an enlarged portion disposed above said chamber and forming a large cylinder, said valve having an upper end defining a piston slidably mounted in said large cylinder, said spring being contained in said large cylinder and bearing against the said last mentioned piston, said large cylinder having a space disposed beneath the last mentioned piston in which a partial vacuum is created by movement of the valve to an open position for cooperation with the spring and the pressure in the large cylinder for urging the valve toward a closed position, and said valve having an inlet port registering with the inlet of the body in an open position of the valve and with a passageway of said tubular member which opens through said last mentioned piston.

2. A regulator adapted to be mounted in a tubing of a well for reducing the pressure of -a well fluid in the tubing above the regulator relative to the pressure thereof beneath the regulator, said regulator comprising a body having a passage for the fluid including an inlet and an outlet disposed above the inlet, a valve mounted in the passage for up-and-down movement, a spring contained in the passage for urging the valve downwardly to a closed position for shutting ofi the fluid flow between the inlet and outlet and to prevent movement of the valve upwardly beyond a fully open position, said passage including a chamber into the upper end of which said valve extends said chamber being adapted to be pressurized by the pressure of the well fluid to displace the valve upwardly to an open position to permit the fluid to pass upwardly through said passage from the inlet to the outlet while the pressure in the chamber is greater than the combined pressure of the fluid above the valve and the pressure of said spring, said valve comprising an elongated member having a small piston at one end and a large piston at the opposite end thereof, said chamber consitituting a restricted portion of said passage forming a cylinder for the small piston, said chamber having an open end disposed remote from said outlet, said inlet being dis posed above said chamber, said valve having an inlet port spaced from said small piston and a passage communicating with the inlet port thereof and opening through said large piston, said inlet port registering with the inlet when the valve is in an open position, said first mentioned passage including an enlarged portion forming a large cylinder for said large piston, and said spring being disposed in said last mentioned cylinder and hearing against the large piston for urging the valve away from the outlet and toward a closed position in combination with a partial vacuum in the large cylinder and beneath the large piston.

References Cited by the Examiner UNITED STATES PATENTS 683,388 9/1901 Curtis 137494 2,306,012 12/1942 Campbell 137512 2,644,481 7/ 1953 Perlman 137494 2,831,493 4/1958 Richmond 137496 X 2,903,014 9/1959 Sheppard 137-512 X 3,196,901 7/1965 Phillipps 137494 M. CARY NELSON, Primary Examiner. MARTIN P. SCHWADRON, Examiner. S. SCOTT, Assistant Examiner. 

1. A REGULATOR ADAPTED TO BE MOUNTED IN A TUBING OF A WELL FOR REDUCING THE PRESSURE OF A WELL FLUID IN THE TUBING ABOVE THE REGULATOR RELATIVE TO THE PRESSURE THEREOF BENEATH THE REGULATOR, SAID REGULATOR COMPRISING A BODY HAVING A PASSAGE FOR THE FLUID INCLUDING AN INLET AND AN OUTLET DISPOSED ABOVE THE INLET, A VALVE MOUNTED IN THE PASSAGE FOR UP-AND-DOWN MOVEMENT, A SPRING CONTAINED IN THE PASSAGE FOR URING THE VALVE DOWNWARDLY TO A CLOSED POSITION FOR SHUTTING OFF THE FLUID FLOW BETWEEN THE INLET AND OUTLET AND TO PREVENT MOVEMENT OF THE VALVE UPWARDLY BEYOND A FULLY OPEN POSITION, SAID PASSAGE INCLUDING A CHAMBER INTO THE UPPER END OF WHICH SAID VALVE EXTENDS, SAID CHAMBER BEING ADAPTED TO BE PRESSURIZED BY THE PRESSURE OF THE WELL FLUID TO DISPLACE THE VALVE UPWARDLY TO AN OPEN POSITION TO PERMIT THE FLUID TO PASS UPWARDLY THROUGH SAID PASSAGE FROM THE INLET TO THE OUTLET WHILE THE PRESSURE IN THE CHAMBER IS GREATER THAN THE COMBINED PRESSURE OF THE FLUID ABOVE THE VALVE AND THE PRESSURE OF SAID SPRING, SAID VALVE COMPRISING AN ELONGATED TUBULAR MEMBER HAVING A CLOSED LOWER END DEFINING A LOWER PISTON, SAID CHAMBER CONSTITUTING A RESTRICTED LOWER PORTION OF THE PASSAGE IN WHICH SAID PISTON IS SLIDABLY MOUNTED, SAID CHAMBER HAVING AN OPEN LOWER END OPENING OUTWARDLY OF THE BODY BENEATH THE LOWER PISTON, SAID INLET OPENING INTO THE PASSAGE ABOVE SAID LOWER PISTON, SAID PASSAGE INCLUDING AN ENLARGED PORTION DISPOSED ABOVE SAID CHAMBER AND FORMING A LARGE CYLINDER, SAID VALVE HAVING AN UPPER END DEFINING A PISTON SLIDABLY MOUNTED IN SAID LARGE CYLINDER, SAID SPRING BEING CONTAINED IN SAID LARGE CYLINDER AND BEARING AGAINST THE SAID LAST MENTIONED PISTION, SAID LARGE CYLINDER HAVING A SPACE 